中国菊花石的矿物组成特征

中国菊花石产于二叠纪栖霞组碳酸盐岩层位中,菊花石经光学显微鉴定,Ｘ－射线衍射分析和ｘ－射线能谱仪测试,其原生矿物主要天青石和菱锶矿,两种含锶矿物后期广泛被方解石,白云石和石英交代,依据其菊花石原生矿物组成,将我国菊花石划分为天青石型（浏阳菊花石为典型）菱锶矿型（宣恩,来宾菊花石）和青青石－菱锶矿混合型（永丰型菊花石）菊花石三种类型。     

柴达木盆地西北部大风山天青石矿床地球化学特征及成矿物源属性探讨

柴达木盆地西北部地区上新世湖相沉积中发育有我国储量最大的内陆湖相蒸发岩型天青石矿床,长期以来针对该矿床主要进行了地质勘查与开发,而对于大风山天青石矿的成矿物源及成因模式方面的研究工作相对较少。本文通过对大风山天青石矿床短轴复式背斜之北翼、轴部及南翼典型蒸发岩剖面进行系统研究,结合前人相关锶同位素数据特征和区域地质资料,利用柴达木盆地内现代河流锶含量的分布特征,蒸发岩剖面的主量元素特征及岩石薄片分析等手段,对大风山天青石矿床的成矿物质来源及矿床成因进行了一定程度的探讨,主要得出以下结论:(1)柴达木盆地周缘长英质基岩长期的风化作用为湖相天青石矿的形成提供了主要锶源;(2)围岩富锶碳酸盐岩显著发育的溶蚀与交代作用对天青石矿物的二次富集起到了重要作用;(3)高山深盆构造背景下的振荡干化作用有利于沉积物中锶的溶解迁移与富集成矿。     

我国锶矿的成因类型及找矿方向

<正> 我国锶矿资源丰富,矿床成因类型比较齐全。本文是笔者对我国主要锶矿床勘查、研究、考察的基础上编写的。在此对向本文提供过资料的江苏、内蒙古、青海、湖北及云南省(区)地质矿产局表示感谢! 一、锶的地球化学及矿床成因分类锶属碱土稀有金属,其克拉克值为0.048％,富集成矿不多。锶在岩浆、热液、沉积、后生及表生阶段均有活动和富集。其工业矿物主要为天青石和少量菱锶矿。     

甘肃省锶矿泉水的富集环境及其形成机理研究

甘肃省位于中国四大地理区（北方区、南方区、西北区和青藏高原区）的相接部位,气候类型多样、地质构造活动强烈、地形复杂、地貌形态多样,复杂的地质条件、多样的地理气候环境和水文地质条件,为锶矿泉水的形成提供了有利条件。通过对全省644个水点的样品检测分析,表明锶含量主要集中在0.09~1.00 mg/L,最高值达15.6 mg/L,锶含量≥0.40 mg/L、达到饮用天然矿泉水界限含量的水点共有411个,占全部水点的58.1%,锶是甘肃省地下水中普遍含有并且含量较丰的微量元素之一。经统计分析表明,在水文地质单元上,以山前盆地第四系地下水为主的河西走廊平原区和以白垩系碎屑岩孔隙裂隙水为主的陇东黄土丘陵区地下水中最有利于锶的富集;地下水类型上,以中新生界碎屑岩地下水锶最易富集,而以变质岩为主的基岩裂隙水不利于锶的富集;循环特征上,以具备深循环条件的盆地型地下水系统最有利于锶的富集,而循环路径短、交替条件较强烈的局部水流系统中地下水锶偏贫。围岩中的锶丰度,决定了地下水中锶的含量,白垩系和新近系碎屑岩、古生界碳酸盐岩中锶丰度高,决定了白垩系碎屑岩地下水、新近系碎屑岩地下水和碳酸盐岩岩溶水具备锶矿泉水富集的物质条件;同时锶在地下水中富集,还与地下水所处的构造环境和地下水循环运移特征有关,盆地型的地下水流系统和进行深循环的地下水从补给区到排泄区径流距离远,循环路径长,地下水在含水层的滞留时间长,有利于锶在地下水中的溶解和富集。     

滦河流域中上游富锶地下水成因类型与形成机制

承德市滦河流域富锶矿泉水资源丰富,成因类型多样,具有典型研究意义。通过水化学图解与多元统计分析、离子比值分析、矿物平衡体系分析,分析富锶地下水形成的地球化学背景,分区阐述富锶地下水水化学特征,探讨富锶地下水的形成机制。结果表明,研究区水化学类型以HCO3-Ca·Mg、HCO3·SO4-Ca、HCO3-Ca、HCO3·SO4-Ca·Mg为主。富锶地下水的形成受地质构造格局和岩浆活动控制,地质建造锶元素丰度影响,水文地球化学条件制约。断裂构造和地层岩性控制着富锶地下水形成分布的总体特征,水文地质条件影响着地下水化学锶元素的地球化学响应机制。地下水锶富集来源为含水介质长石矿物、碳酸盐矿物的风化溶解和阳离子交换吸附作用,矿泉水出露机制分为构造断裂深循环淋溶型、裂隙浅循环淋溶型、补给富集埋藏型3种类型。坝上高原孔隙裂隙水系统富锶地下水形成作用主要受大气降水和溶滤作用控制,滦河中上游裂隙水系统地下水阳离子交换吸附作用强烈,滦河中游孔隙岩溶裂隙水系统地下水化学主要受溶滤作用控制,蒸发浓缩作用和人为活动影响。     

兰坪金顶白草坪矿区天青石工艺矿物学特征及可选性研究

天青石是制取各种锶化合物的主要原料.本文通过显微镜观察、扫描电镜能谱分析、化学多元素分析、摇床重选等手段,研究了云南兰坪县金顶白草坪天青石矿工艺矿物学特征和可选性.结果表明,矿石中天青石为锶元素赋存的目的矿物,呈板状,粒度为中-粗粒级,含锶高达50.24％.采用摇床重选工艺和-0.2mm的入选细度可有效富集天青石.     

华东某锶矿床地质特征及其成因初探

目前已知含锶矿物有十余种.它的独立矿物只有天青石(SrSO_4)和菱锶矿(SrCO_3),是提取锶的主要原料.锶在地球上的平均含量很低,据克拉克和华盛顿为170ppm. 锶的用途很广.它可用做原子电池、特种合金,改进生铁性质、难熔金属还原剂;锶盐常用     

南大巴山前缘黄龙组古岩溶储层锶同位素地球化学特征

南大巴山前缘黄龙组古岩溶储层划分为弱溶蚀岩溶岩、中等溶蚀多孔状岩溶岩、强溶蚀角砾状岩溶岩和强溶蚀交代的次生灰质岩溶岩等4种类型,以非溶蚀岩为对比参照物,系统分析了各类岩溶岩的锶同位素组成.结果表明:岩溶过程中的87Sr/86Sr值,具有从渗流-活跃潜流带的正偏移,至静滞潜流带逐渐转化为强烈负偏移的演化趋势;在同一岩溶水流体的水-岩反应体系中,基质组分相比角砾对87Sr的富集作用更强,而次生灰质岩溶岩相比白云质岩溶岩缺乏富集87Sr的锶同位素分馏效应;不同成因类型和溶蚀强度的岩溶岩具有高87Sr/86Sr值特征,主要与参与古岩溶作用水-岩反应的古陆地下水富87Sr壳源锶的注入以及白云质基质岩对87Sr具有强富集作用有关.各类岩溶岩锶同位素特征,可为预测和评价研究区黄龙组古岩溶储层发育条件及时空展布规律提供地球化学信息.     

蒸发岩建造与天青石矿床

<正> 虽然锶在地壳中的平均含量为0.048%(黎彤,1976),但却很少富集成矿,以致有人将锶划归为稀有金属。在自然界三十多种含锶矿物中,最重要的是天青石(SrSO_4)。目前国内外已发现的最有工业价值的天青石矿床大多产在蒸发岩建造中。这绝非偶然,值得探讨。一、与天青石矿床有关的蒸发岩建造的类型通过分析国内外天青石矿床的地质资料,发现天青石矿床所处大地构造位置及各种     

沉积型天青石矿床的地质特征及其成因探讨

沉积型天青石矿床和蒸发岩类 ,特别是石膏的沉积密切相关 ,含矿地层主要是纹层状叠层石或藻灰岩。天青石中硫、锶同位素值和海水硫、锶同位素值相近。在蒸发条件下海水浓缩到一定浓度时 ,产生天青石沉积 ,或是富锶的硫酸型晶间卤水和钙碳酸盐反应 ,形成交代型天青石。天青石主要分布于蒸发盐盆地的边缘部位 ,位于钙碳酸盐和钙硫酸盐沉积的过渡带     

Geochemical evolution of groundwater in carbonate aquifers in Taiyuan, northern China

Thirty-nine samples of both cold and thermal karst groundwater from Taiyuan, northern China were collected and analyzed with the aim of developing a better understanding of the geochemical processes that control the groundwater quality evolution in the region’s carbonate aquifers. The region’s karst groundwater system was divided into three geologically distinct sub-systems, namely, the Xishan Mountain karst groundwater subsystem (XMK), the Dongshan Mountain karst groundwater subsystem (DMK) and the Beishan Mountain karst groundwater subsystem (BMK). Hydrochemical properties of the karst groundwaters evolve from the recharge zones towards the cold water discharge zones and further towards the thermal water discharge zones. In the XMK and the DMK, the hydrochemical type of the groundwater evolves from HCO₃-Ca·Mg in the recharge - flow-through zone, to HCO₃·SO₄-Ca·Mg/SO₄·HCO₃-Ca·Mg in the cold water discharge zone, and further to SO₄-Ca·Mg in the thermal water discharge zone. By contrast, the water type changes from HCO₃-Ca·Mg to HCO₃·SO₄-Ca·Mg in the BMK, with almost invariable TDS and temperatures all along from the recharge to the discharge zone. The concentrations of Sr, Si, Fe, F⁻ and of some trace elements (Al, B, Li, Mn, Mo, Co, Ni) increase as groundwater temperature increases. Different hydrogeochemical processes occur in the three karst groundwater sub-systems. In the XMK and the DMK, the geochemical evolution of the groundwater is jointly controlled by carbonate dissolution/precipitation, gypsum dissolution and dedolomitization, while only calcite and dolomite dissolution/precipitation occurs in the BMK without dedolomitization. The hydrogeochemical data of the karst groundwaters were used to construct individual geochemical reaction models for each of the three different karst groundwater sub-systems. The modeling results confirm that dedolomization is the major process controlling hydrochemical changes in the XMK and the DMK. In the thermal groundwaters, the dissolution rates of fluorite, siderite and strontianite were found to exceed those of the cold karst groundwater systems, which can explain the higher concentrations of F⁻, Fe and Sr²⁺ that are found in these waters.     

青海大风山天青石矿床地质特征及成因分析

大风山天青石矿床位于柴达木盆地西北部,由Ⅰ、Ⅱ、Ⅲ、Ⅳ四个矿区组成,赋矿地层为第三系上新统狮子沟组,含矿层位不稳定,矿体多呈薄层状、扁豆状或透镜状产于含碳钙质泥岩中,矿石主要为天青石、菱Sr矿等;矿区内东西、北东东向次级断裂及舒缓短轴复式背斜构造严格控制着天青石矿体的产出形态;成矿物源具有多源性,一方面周边山系含Sr水为主要补给源,其次为富Sr的油田水。另外,深部含Sr卤水的补给也具有重要作用;矿床成因具有陆相湖泊化学沉积-热水沉积叠加改造型矿床特征。     

High arsenic and boron concentrations in groundwaters related to mining activity in the Bigadiç borate deposits (Western Turkey)

This study documents the environmental impacts of borate mines in Bigadiç district, which are the largest colemanite and ulexite deposits in the world. Borate-bearing formations have affected the concentrations of some contaminants in groundwater. Groundwater quality is directly related to the borate zones in the mines as a result of water–rock interaction processes. Calcium is the dominant cation and waters are Ca–SO₄ and HCO₃ type in the mine (Tülü borate mine) from which colemanite is produced. However in the Simav and Acep Borate Mines, ulexite and colemanite minerals are produced and waters from these open pit mines are Na–HCO₃–SO₄ types. High SO₄ concentrations (reaching 519 mg/L) might be explained by the existence of anhydrite, gypsum and celestite minerals in the borate zone. Groundwater from tuff and borate strata showed relatively low pH values (7–8) compared to surface and mine waters (>8). EC values ranged from 270 to 2850 μS/cm. Boron and As were the two important contaminants determined in the groundwaters around the Bigadiç borate mines. Arsenic is the major pollutant and it ranged from 33 to 911 μg/L in the groundwater samples. The concentrations of B in the study area ranged from 0.05 to 391 mg/L. The highest B concentrations were detected at the mine areas. The extension of the borate zones in the aquifer systems is the essential factor in the enrichment of B and As, and some major and trace elements in groundwaters are directly related to the leaching of the host rock which are mainly composed of tuffs and limestones. According to drinking water standards, all of the samples exceed the tolerance limit for As. Copper, Mn, Zn and Li values are enriched but do not exceed the drinking water standards. Sulfate, Al and Fe concentrations are above the drinking water standard for the groundwater samples.     

鲁中南岩溶水资源综合类型及合理调蓄研究

鲁中南岩溶区是中国北方半干旱温带岩溶区中具有代表性的地区之一。该区岩水资源分布具有明显的不均匀性和大面积分散补给而局部富集等特征。岩溶形态以溶蚀裂隙洞穴为主，地下水类型多为裂隙溶洞型。在对该区岩溶水补给，富集，径流及排泄特征的研究基础上，初步将本区地表水和地下水资源划分为两大类型，即地下岩溶水径带变化带水资源类型和排泄带水资源及地下岩溶水资源类型。对该地区地表水和地下水的合理调蓄问题进行了系统的分析和总结，并提出了相关的对策。     

安徽马鞍山市当涂地区地下水水化学特征及演化机制

【研究目的】 了解长江中下游平原地区地下水流系统并深入分析其地下水水化学特征及其演化机制。【研究方法】 综合马鞍山市当涂地区的水文地质条件、水动力场等,基于研究区水化学基本特征,运用多元统计分析、水化学图件、离子比值和反向水文地球化学模拟等方法对该地区浅层地下水水化学演化进行分析。【研究结果】 结果表明：（1）研究区地下水主要为低矿化度偏碱性水,地下水组分中阳离子以Ca²⁺和Mg²⁺为主,阴离子以HCO₃^-和SO₄^2-为主。（2）研究区地下水水化学类型主要可分为7类,其中松散岩类孔隙含水岩组和碎屑岩类孔隙裂隙含水岩组的水化学类型主要为HCO₃^-Ca型、HCO₃^-Ca·Na型、HCO₃·Cl-Ca·Na型以及HCO₃^-Ca·Mg型;基岩类裂隙含水岩组的化学类型主要为HCO₃·SO₄-Ca·Mg型和SO₄·HCO₃^-Ca·Mg型。（3）研究区浅层地下水水样超标率为46%,总体水质较差,超标率较高的组分依次为Mn、高锰酸盐指数（COD_Mn）、硝酸盐（以N计）、Fe、As、氨氮（以N计）等。（4）研究区地下水的化学组分主要受到岩石风化作用的控制;此外,还存在Na-Ca的正向阳离子交替吸附作用。反向水文地球化学模拟结果进一步定量论证了水岩相互作用对本区浅层地下水组分的形成和演化起着主导作用。【结论】 研究区地下水主要为低矿化度偏碱性,主要可分为松散岩类孔隙水、碎屑岩类孔隙裂隙水和基岩类裂隙水。主要离子比例和反向水文地球化学模拟揭示了本区浅层地下水化学组分主要是地下水溶滤方解石、白云石等碳酸盐矿物、石英、长石等硅酸盐矿物,高岭土等黏土矿物以及岩盐、石膏等达到过饱和之后形成的。     

Identifying the Sources of Solutes in Karst Groundwater in Chongqing,China: a Combined Sulfate and Strontium Isotope Approach

Groundwater from karst subterranean streams is among the world’s most important sources of drinking water supplies, and the hydrochemical characteristics of karst water are impacted by both natural environment and people. Therefore, the study of hydrochemistry and its solutes’ sources is very important to ensure the normal function of life support systems. In this paper, thirty?five representative karst groundwater samples were collected from different aquifers (limestone and dolomite) and various land use types in Chongqing to trace the sources of solutes and relative hydrochemical processes. Hydrogeochemical types of karst groundwater in Chongqing were mainly of the Ca?HCO3 type or Ca (Mg)?HCO3 type. However, some hydrochemical types of karst groundwater were the K+Na+Ca?SO4 type (G25 site) or Ca?HCO3+SO4 type (G26 and G14 site), indicating that the hydrochemistry of these sites might be strongly influenced by anthropogenic activities or unique geological characteristics. The dissolved Sr concentrations of the studied groundwater ranged from 0.57 to 15.06 μmmol/L, and the 87Sr/86Sr varied from 0.70751 to 0.71627. The δ34S?SO42? fell into a range of ?6.8‰?21.5‰, with a mean value of 5.6‰. The variations of both 87Sr/86Sr and Sr values of the groundwater samples indicated that the Sr element was controlled by the weathering of limestone, dolomite and silicate rock. However, the figure of 87Sr/86Sr vs. Sr2+/[K++Na+] showed that the anthropogenic inputs also obviously contributed to the Sr contents. For tracing the detailed anthropogenic effects, we traced the sources of solutes collected karst groundwater samples in Chongqing according to the δ34S value of potential sulfate sources. The variations of both δ34S and 1/SO42? values of the groundwater samples indicated that the atmospheric acid deposition (AAD), dissolution of gypsum (GD), oxidation of sul?de mineral (OS) or anthropogenic inputs (SF: sewage or fertilizer) have contributed to solutes in karst groundwater. The influence of oxidation of sul?de mineral, atmospheric acid deposit and anthropogenic inputs to groundwater in Chongqing karst areas was much widespread.     

Preliminary study on strontium-rich characteristics of shallow groundwater in Dingtao Area,China

Based on the analysis of element correlation, the Gibbs diagram, hydro-geochemical ion ratios, isoline maps of groundwater and soil, and change patterns of strontium content after normalization, the study examines water-rock interaction of shallow groundwater in Dingtao area. The results suggest that strontium in the study area mainly comes from water-rock interactions, and the strata interacting with groundwater are the top of Quaternary and Neogene. The element correlation analysis shows that the formation of strontium-rich groundwater is sufficiently affected by sulfate and carbonate. The Gibbs diagram suggests that the chemical composition of groundwater is mainly influenced by water-rock interactions, accompanied by evaporation crystallization. c(Ca²⁺+Mg²⁺)/c(HCO₃^-+SO₄^2-) reflects that the main reactions in the groundwater system is weathering dissolution of carbonate and sulfate, and ion exchange takes place. c(Na⁺)/c(Cl^-) indicates that Na⁺ in groundwater may have water-rock interactions with rocks it flows through. c(Cl^-)/c(Ca²⁺) indicates that the hydrodynamic condition in the pumping well is poor and the water circulation is slow. The study examines the macro isoline map change patterns, correlation curves of change of strontium content in groundwater and shallow soil, and correlation curves of change of strontium content in groundwater, shallow soil, and deep soil. The results suggest that the strontium content in the study area has the same change pattern in groundwater and in soil, which further indicates that strontium in the study area comes from water-rock interactions.     

山东大汶河流域中上游古近系含水岩组水文地质特征

利用古近系大汶口组及朱家沟组含水岩组5眼施工钻孔及55眼井孔调查资料,通过岩心、地下水常规离子组分及氢氧同位素样品测试结果,研究大汶河流域中上游莱芜盆地、大汶口盆地古近系含水岩组分布特征、物性及富水性、地下水化学及补给循环特征。结果表明:富水较好的大汶口组上段位于盆地腹部偏北,含水层岩性为半固结砂砾岩,水化学类型HCO_3-Ca·Mg型为主;朱家沟组含水岩组位于盆地边界断裂下降盘,含水层岩性为溶蚀发育的灰质砾岩,水化学类型复杂多变。现代大气降水作为地下水主要补给来源,蒸发浓缩作用,方解石、白云石和石膏溶解及人类污染活动参与了地下水化学组分的形成。归纳总结3种古近系不同类型含水岩组地下水富集规律:构造裂隙控水模式、半固结含水岩组裂隙孔隙水富集模式和灰质砾岩裂隙岩溶水富集模式。     

Statistical and geochemical assessment of groundwater quality in Teboursouk area (Northwestern Tunisian Atlas)

Teboursouk region, Northwestern Tunisia, is characterized by the diversity of its natural resources (petroleum, groundwater and minerals). It constitutes a particular site widely studied, especially from a tectonic stand point as it exhibits a complex architecture dominated by multi-scale synclinals and Triassic extrusions. It has typical karst landform that constitutes important water resources devoted for human consumption and agriculture activities, besides to the exploitation of the Mio-Plio-Quaternary aquifer (MPQ). Thus, hydrogeological investigations play a significant role in the assessment of groundwater mineralization and the evaluation of the used water quality for different purposes. Hence, the current study based on a combined geochemical–statistical investigation of 50 groundwater samples from the multilayered aquifer system in the study area give crucial information about the principal factors and processes influencing groundwater chemistry. The chemical analysis of the water samples showed that Teboursouk groundwater is dominantly of Ca–Mg–Cl–SO₄ water type with little contribution of Ca–Mg–HCO₃, Na–K–Cl–SO₄ and Na–K–HCO₃. The total dissolved solids (TDS) values range from 0.37 to 3.58 g/l. The highest values are located near the Triassic outcrops. Furthermore, the hydrogeochemistry of the studied system was linked with various processes such as carbonates weathering, evaporites dissolution of Triassic outcrops and anthropogenic activities (nitrate contamination). Additionally, the main processes controlling Teboursouk water system were examined by means of multivariate statistical analysis (PCA and HCA) applied in this study based on 10 physicochemical parameters (TDS, pH, SO₄, HCO₃, pCO₂, Ca, Mg, Na, K, Cl and NO₃). Two principal components were extracted from PCA accounting 61% of total variance and revealing that the chemical characteristics of groundwater in the region were acquired through carbonates and evaporite dissolution besides to nitrate contamination. Similarly, according to Cluster analysis using Ward’s method and squared Euclidean distance, groundwater from the studied basin belongs to five different groups suggesting that the geochemical evolution of Teboursouk groundwater is controlled by dissolution of carbonates minerals, chemical weathering of Triassic evaporite outcrops, cation exchange and anthropogenic activities (nitrate contamination).